Professor Ledger explains loans, interest and promissory notes
Ages 6+eBook available now
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The Promise to Pay is a children’s book about loans for readers ages 6 and up. Professor Ledger, the kind Wealthonauts robot, explains what it means to borrow, why lenders charge interest and why a written promise, called a promissory note, matters. It is the second book in The Wealthonauts Adventures.
About this children’s book about loans
Pip wants to fix the space-scooter before the big race, but Pip doesn’t have enough coins. Captain Coin can lend them, and Professor Ledger insists they write the deal down. Together, they decide the amount, the extra cost of borrowing and the due date. Then Pip works hard to keep the promise.
Why it stands out
Many books teach saving, but few explain borrowing clearly. This story introduces principal, interest and due dates with friendly characters and a simple written note. In addition, it shows what happens when a payment is late and why keeping promises builds trust. Every term in the book matches the lesson on this site.
Using this children’s book about loans at home or in class
Read one chapter or spread at a time, then pause and ask what the characters should do next. Afterward, open the matching free lessons below for activities at three age levels. Teachers can pair this children’s book about loans with the printable worksheets in the Academy.
Best🎓Take the matching lessonsThe same topics, in the Wealthonauts course for your child’s age — with quizzes, tracking and a game. Included in All-Access.What Is a Promissory Note?
Formats and pricing
Digital eBook (read online)$7.99Read instantly online after checkout
eBook + All-Access courses$103.99Save $3.00Read the book online + every course (All-Access), one payment
Paperback$13.99Coming soon
Purchases are completed by a parent or guardian at checkout. eBooks are read online: open them from the order confirmation page, the confirmation email or My account → My books.
What kids will learn
Explain borrowing and repaying in simple words
Identify principal, interest and a due date
Understand what a promissory note is
Connect keeping promises with trust
For parents and teachers
After reading, write a pretend note together (“I promise to return 5 stickers by Friday”) and sign it. Older kids can try the Ages 8+ level of What Is a Promissory Note? This book is educational; real loan documents should be reviewed by an adult.
Preview pages
Sample story text from the book.
Page 1
Pip’s space-scooter had a wobbly wheel.
The race was on Saturday.
A new wheel cost ten coins.
Pip had only six.
Page 2
“I can lend you four coins,” said Captain Coin.
“Let’s write it down,” beeped Professor Ledger.
“A promise on paper is a promise everyone can remember.”
Page 3
I, Pip, promise to pay Captain Coin
four coins, plus one extra coin for borrowing,
by next Friday.
Signed, Pip.
“That extra coin is called interest,” said Professor Ledger.
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